Apparatus for separating and cleaning materials



- July 13, 1937. E. sump 2,086,584

APPARATUS FOR SEPARATING AND CLEANING MATERIALS Filed July 29, l952 3Sheets-Sheet 1 one 000000 In were zar Maya/216341 July 13 1937. E. S UMP2,086,584

APPARATUS FOR SEPARATING AND CLEANING MATERIALS Filed July 29, 1932 3sheetsf shee'b 2 /Z4 A A74 E. STUMP 2,086,584

APPARATUS FOR SEPARATING AND CLEANING MATERIALS July 13, 1937.

Filed July 29, 1932 3 Sheets-Sheet 3 In vefi' for r! ,6?

?atented July 13, 1937 STATES RElSSllED PAT APPARATUS FOR SEPARATKNG ANDCLEAN- IING MZSTERIQLS Earl Stump, Chicago,

lilL, assignor to Roberts and Schaefcr Company, Chicago, 1111., acorporation of llllinois Application July 29,

Claims.

My invention relates primarily to apparatus for gravitally separatingparticles of different specific gravities and while it is especiallyapplicable to the cleaning of coal by air, it is useful in con- 5nection with separating other materials both by the use of air and otherfluid separating mediums.

One object of my invention is to provide a machine which can be appliedto the separation of fragmentary materials in one operation through arelatively Wide range of sizing, thereby dispensing with the necessityof excessive preliminary screening.

Another object is to provide a material separating device which, will besimple, light, inexpensive, of large capacity, take up a minimum of roomand have a minimum of vibration whereby it becomes unnecessary to buildspecial reinforcing or stiffened buildings or structures to house thesame. Other objects of my invention will appear from time to timethroughout the specification and claims.

My invention is illustrated more or less diagrammatically in theaccompanying drawings, wherein-'- Figure 1 is a side elevation;

Figure 2is a plan view;

ure 2;

Figure 4 isa section along the Figure 2;

Figure-5 is a detail of the butterfly valve drive;

Figure 6 is a diagrammatic view of a variant form of blower or pump.

Figure '7 is a modified form of the device.

throughout the several figures. A is an air chamber. It has a bottom Aend walls A A side walls A. It is bounded at the top by a perforate wallA A is an air duct discharging into the chamber A. Air is supplied to itand discharged therethrough by a fan or other suitable source'of airunder pressure A". The fan is driven by a motor A in the usual manner. Ais a butterfly valve interposed in the duct A between the fan and thechamber. A is a power transmission interposed between the motor and thebutterfly valve which may be 'of any suitable form but preferably isadapted for easy and convenient speed adjustment so that the revolutionsper minute of the butterfly valve may be conveniently and easilyadjusted during operation of the machine.

Mounted on top of the air chamber A and between the side walls A'? whichproject upwardly above the chamber is a fixed resistance bed B,

Figure 3 is a section along the line 3-3 of Fig line 4-4 of Like partsare indicated by like characters 1932, Serial No. 625,767

formed preferably of screened gravel, shot sawdust, mineral wool or anysuitable material. This resistance bed is bounded at its upper side by aperforate screen or deck B The deck B is inclined to" the wall A so thatthe thickness of the air'resistance bed or filter decrease from one endto the other. The perforate plates B and A are fixed in position and sorelated with the resistance bed that the material therein remains atrest and furnishes at all times a fixed unchanging internal resistancebed to control therate at which air escapes from the chamber A and so tocontrol the pressure of air available along the deck surface B The wallsA project above the deck surface B to form a trough bounded on its underside by the perforate plate B which plate is as indicated downwardlyinclined. B is an auxiliary air chamber located beyond the chamber A andjoined to it by a plurality of bleeder pipes B of such size that the airpressure in the chambers A and B is substantially the same. This chamberB is bounded on its opposed sides by the Walls A which extend forwardlyfrom the chamber A for that purpose and is bounded at its top by aperforate plate Blfl. B is the end Wall of the device. It forms the endwall for the chamber B projects upwardly thereabove to a point above thelower end of the deck B and terminates in a weir or plate B mounted forvertical adjustment. B is a tailings discharge passage. It extends clearacross the machine between the side walls A. It is bounded at the rearby the wall A at the front by the rear wall 13'' of the air chamber BThis channel B inclines forwardly as indicated at B along the under sideof the chamber 13 and is closed by a pivoted flap gate B C is an airpipe. It communicates to one end with the interior of the chamber A. Itterminates in a goose-neck C and. has a discharge end C passing upthrough a water or liquid reservoir C to terminate above the lever C ofthe fluid in the reservoir where it discharges into a float cup C whichcup is immersed in the fluid. C C are adjustable weights mounted on thefloat cup C and C is a lever arm interposed between the cup C and theshaft C which carries the pivoted flap gate B so that movement of thecup will move the flap gate.

The drive for the butterfly valve shown in Figure 5 comprises opposedpairs of conical driving wheels D D D D. A lever D varies in oppositionto the distance between the conical wheels of each pair. D is a flexiblebelt engaged between the opposed faces of these wheels so that as onepair approach toward and the other pair recede from one another, theflexible belt rides out further from the center of rotation from onepair of wheels and closer to the center of rotation of the other pair sothat by this method an accurate control of the speed of the butterflyvalve is obtained.

E is a baffle plate extending clear across the deck, above the refusedischarge opening. It is preferably so positioned that it will beembedded in the refuse and always have above it and between it and thecoal a bed of refuse material.

In the modified form of the device, there 'is substituted for the fanand butterfly valve a Roots type blower F having vanes F F driven by amotor F the speed of which can be controlled in any suitable manner. TheRoots type blower being a positive displacement pump insures positiveimpulses to the air without the interposition of the butterfly valve andsuch a device as this can under some circumstances be used to displace aliquid rather than a gaseous fluid so that if water or other similarliquid is used, the same pulsating effect may be obtained.

The variant speed drive has been shown merely as illustrative of anysuitable type of variable speed drive. It is understood that manydifferent types may be used.

Intermediate between the air box and the control cup or control meansis'located the valve G which may be manually set to initially adjust theresponse of the control cup or member and so the response of thedischarge means to the air pressure in the air flow box. It will beunder-- stood of course that when the device is in operation, thecontrol cup constantly pulsates and there is, a constant opening andclosing or movementiri the direction of opening and closing of therefuse valve. This is of course caused by the pulsations of variationsin pressure in theair flow caused or imparted by the butterfly valve orother suitable means. This vibratory or pulsating movement of the refusegate is of course important in that it tends to break up anyaccumulations of refuse in the discharge chamber.

The high resistance bed is preferably of marbles or shot or some smoothgenerally spherical objects because while experience shows that so faras the control of the air pressure itself is concerned, most anyresistance medium will do, the great difficulty lies in obtaining aresistance medium which will give the desired resistance to air flow andstill will be immune from clogging by dust. This is of the utmostimportance because experience shows that this clo ing takes place bothas a result of dust entrained by the air as it passes upwardly throughthe resistance bed and also as a result of dust passing down from thetreating deck into the resistance bed, being there lodged and caught andheld when the air is turned off and the bed ceases to operate.

The smooth walled passages are'essential to prevent this clogging. Theydo not need to be perfectly straight, they can well be of constantlyvarying cross section because if the walls are rough, dust particlescatch, adhere and build up and it is preferably better to have them ofvarying cross section because if the cross section should be constant,there would be too little resistance to air flow and not enough eddycurrents in the bed itself and also there would be a greater chance ofrefuse bridging or clogging in such minute passages.

' Figure '7 shows a modified form of the device wherein the air chamberB pipes B perforate plate B the refuse passage B the baffle plate E areall dispensed with. At the end of the deck B is a refuse chute H. therefuse gate H is pivoted thereon, being controlled in exactly the samemanner and by the same mechanism as the refuse gate C shown in Figure 6.The coal or lighter material passes off in the same direction, that is,parallel with the axis of the table over the coal chute H A weir H isadjustable horizontally to control the coal stream. A plate H isadjustable horizontally to control the refuse stream. Plates H H areindependently adjustable and between them and in cooperation with therefuse gate H they control the relative proportions of material flowingto the refuse and coal chutes or through the concentrate and the ganguechutes as the case may be. The important thing is that the adjustment ofthe gates H H may be experimental adjustments only, that is to say, theydepend on the size of the material being treated and its particular,peculiar characteristics.v The adjustment once made when the plant isbuilt, never again needs to be made. So it is possible that when theadjustment has been made, to take it off and put a single plate insteadof the two adjustable plates H H which plate will be welded or rivetedin place.

It is hooded at H and This plate intersecting the line of flow of the iand when handling coal as it comes from the mine, the horizontal line ofcleavage between the refuse bed and the coal bed as they travel down thedeck is likely to vary. In the past, it has been necessary to veryclosely position and watch the dividing member to insure that'coal didnot come out with the refuse when the refuse bed got thin or that refusedid not come out with the coal when the coal bed got thin. My structurewith this relatively broad plate insures that the refuse is taken fromthe bottom of-the refuse bed and coal taken from the top of the coal bedand a very considerable vertical deviation or de-- flection of thedividing line between the two beds may take place without interferingwith the product.

It will be understood also that the mechanism for supplying air to theflow box, the mechanism for causing the pulsation of air and themechanism for permitting pressure variations and pressure pulsations tothe refuse gate all may.

be varied without departing from the general principles of operation ofmy device. The use and operation of my invention are as follows: I

With the device .set up as indicated in the drawings, the fan is startedforcing air under pressure into the air chamber. At the same time thebutterfly valve rotates. This butterfly valve is so arranged that evenwhen in the closed position it does not entirely out off the flow ofair. As it rotates it thus increases and decreases any alternationperiodically the amount of air fed to the air chamber, thus causing thepressure in the chamber to vary at a con-' trolled rate of speed and theair always flows up through the fixed resistance bed but the pressureavailable pulsates or varies between a minimum and a maximum. There isnever any backward movement of the air in the direction of theresistance'bed but always outward 2,080,584 3 moverLent of the air thrugh the bed and through or pipes B to pass into the refuse bed which thedeck. is below or beyond the refuse spout, to the right Coal or othersuitable material is then fed through the spout as indicated onto theupper end of the deck, that is to say, into the trough formed betweenthe perforate deck and the side walls. This material flows down in acontinuous stream through the trough being pulsating or vibratingvertically as it flows generally horiof the float cup which-controls thedegree of zontally under the influence of gravity, no vi-. bration ofthe device itself occurring or being desired. The pulsating air streamsets up -a vibration in the body of flowing material giving it a liquidor fluid characteristic much greater than without the pulsating airflow. This liquid characteristic being sufllcient to enable the heavierparticles as the flow goes on to gravitate to the bottom and the lighterparticles to the top. This forms a bed which'toward the lower endconsists in light material or coal at the top supported on heaviermaterial, refuse, slate or the like at the bottom as indicated in Figure4 of the drawings. This refuse fills up the refuse discharge passage andbuilds up a bed of refuse at the bottom of the machine beneath theflowing stream of coal. As this bed builds up it adds it, together withthe coal and the flowing material on the deck resistance to the escapeof air and causes an increase in air-pressure in the air chamber. Thisincrease in air pressure makes itself felt through the air deck in thecontrol oup'as indicated, thereby raising it and opening the refuse flapvalve wider. It will be understood, of course, that the refuse flapvalve is ordinarily setso that it is always partially open but thisvariation in, pressure in the air chamber caused by variation in theresistance to the escape of the air results in opening or closing therefuse valve more or less so as to maintain toward the lower end of thechute or trough on the lower end of the perforate deck, a bed of refuseof the desired thickness, the coal which by the tim e it reaches thelower end of the chute will have become separated from the refuse, willrun out over the adjustable weir: or gate at the lower end while therefuse runs put through the refuse spout. 4

It will'be noted that beyond the refuse spout is a bank or wall ofrefuse whiclr takes an upwardly inclined the pulsating effect of the airand'provides a live abutment to bound the lower limit of the refusebed.The deflector plate extending as it does horizontally across the refusedischarge opening insures that the refuse runs in from the side and notfrom the top and thus prevents excessive local draining off of therefuse bed which might result in drawing coal down through the refusedischarge. The only adjustmentsthat are necessary are the height of theweir or discharge gate which assists in' controlling the depth of therefuse bed immediately at the coal discharge, the speed of the butterflyvalve which controls the rate of pulsation, andthe weight opening of therefuse discharge gate and the fluid pressure supplied by the fan orpump. Ex-

perience shows that under ordinary conditions when these adjustmentshave been made, the apparatus will thereafter unless change in productor change in the material treated is deslred, continue substantiallywithout change to operate in a satisfactory manner. The perforated plateB permits air pressure from the chamber 1?, which has reached it throughthe bleeder pipe position and. is kept alive by as shown in Figure 4.

In view of the fact that the deck is smooth and unobstructed, there isno tendency toward the hanging or sticking of material on the deck andthe constant. upward movement of air through the perforations in thedeck prevents clogging, plugging or blinding. It is true that wet orsoggy material cannot be as satisfactorily separated on any air deck ascan dry material but the presence of wet or soggy material merelydecreases for a time to alimited extent the separating effect but doesnot interfere with the operation of the device beyond that and moreoveras soon as the wet material has passed off the deck, operation continueswithout change in any essential respect.

If it is desired to usea fluid medium other than air for separation,water, gases or other liquids may be used, being treated in the same wayexceptthat other means may be provided than the butterfly valve forinterrupting the flow or there may be substituted for the butterflyvalve and centrifugal fan, a positive displacement pump which will givea pulsating effect. This is shown diagrammatically in Figure 6.

Preferably, I propose to use a separating fluid medium which is fedthrough the bed of material to be classified pulsatingly in a continuousforward moving current at varying speed which oi course means thatnormally there is always a pressure in the air chamber, the pressure in-.creasing and decreasing periodically. Under some circumstances,however, it may be desirable to use an alternating current, that is, theair or other fluid medium may' go out and the pressure may drop in .theair chamber or fluid containing box below atmospherlc and exert' a backsuction.

It will be noted also that the resistance bed beneath the deck is afixed and the material or particles between the under side of the deckand the perforated plates which form this resistance bed are about thedeck and the plate held in fixed position so that they do not move,vibrate or have any displacement in response to the current ofseparating or floating medium. They merely serve as a part of a fixedimmovable resistance bed.

.The use of the butterfly valve interposed between the fan or pressuresource and the resistance bed because the valve never entirely closesthe aperture, causes this pulsating or current eifect brft since thepump or fan or blower continuously operates the partial interruption ofthe current by the butterfly valve seems to tend to build up excesspressure which as the valve is opened is released thereby increasing thepulsating efi'ect.

I claim:

1. In a concentrator, a downwardly inclined pervious unobstructed deckof constant width, means for feeding a continuous sheet of material bygravity there'across, means for forcing a fluid medium upwardly throughthe deck and the immovably held bed sheet of material thereon, theresistance of which v fluid medium upwardly through such plate, and

aconcentrate chute extending clear across the pervious unobstructeddeckof constant width,

means for feeding a continuous sheet of material by gravity thereacross,means for forcing a fluid medium upwardly through the deck and the sheetof material thereon, a fixed high resistancebed on the underside of thedeck, the resistance of which to fluid fiow decreases toward the lower.edge thereof, and a perforate plate spaced from but in general alignmentwith the lower boundary of the pervious deck and adapted to receive and.support material as it travels across the lower boundary of the deck andmeans for forcing a fluid medium upwardly through such plate, said meanscomprising an air pocket bounded by said plate and an unobstructed airpassage between it and the air chamber, and a concentrate chuteextending clear across the deck and interposed between its lowerboundary and the' perforate perviousi deck, means for feeding a plate, abattle plate generally parallel with the direction of flow of materialalong the deck, spaced above the deck, overlying the refuse. chuteandprojecting on its upstream 'side away from.

the chute to overlie the resistance bed and on its downstream side awayfrom the chute to overlie the perforated plat e.

3. In a concentrator, a

ntinuous sheet of material by gravity thereac oss, means for forcingailuid medium upwardly through the deck and the sheet of materialthereon, a fixed resistance bed on the underside of the deck, the

resistance of which to fluid flow decreases toward deck.

downwardly inclined the loweredge thereof, a weir extending entirely?aross the deck at the lower end thereof and projecting upwardlythereabove over which the tailclear across the deck and between it andthe perforate plate, and a baflle plate overlying the refuse dischargechute generally parallel with the deck and located at a point below theweir. 4. In an air concentrator, an air pervious, material supportingdeck, means for supplying ma-' terial to travel thereacross under theinfluence of gravity, means for effecting a separation of material,toward the discharge end of the deck, along horizontal planes, means forforcing a continuous uninterrupted column of air under pressure upwardlythrough the deck and the bed of materlal'thereon, automatic meansresponsive to variation in the air pressure beneath the deck for varyingthe relative proportions of separated material in the discharge zones asthey leave the 5.'In an air concentrator, an air pervious, materialsupporting deck, means for supplying ma-' terial to travel thereacrossunder the influence 0f gravity, means for efiecting a separation ofmaterial, toward the discharge end of the deck, along horizontal planes,means for forcing a continuous uninterrupted column oi" air underpressure upwardly through the deck and the bed of material thereon andfor imparting a pulsating effect to the air column, automatic meansresponsive to variation in the air pressure beneath the deck for varyingthe relative proportions of separated material in the discharge zones asthey leave the deck, l

' 9 EARL STUMP.

